This is an application for funds to support the publication of the proceedings of a workshop entitled "Needs for New Animal Models of Human Disease". The workshop, to be held in Bethesda, Maryland on April 28 and 29, 1980, will be planned to define the most important criteria of what constitutes reliable models and will determine where some of the major needs are for new animal models. Twenty invited speakers will initiate the discussion, and the entire working group will be limited to about 100. The proceedings will be published as a supplement to the American Journal of Pathology.